Performance Practice
of Electroacoustic Music

Hans Tutschku

pressure – divided


pressure – divided was composed in 2015 and first performed on 26 September 2015 at the Festival “Kontakte” at the Academy of Arts, Berlin with cellist Séverine Ballon, to whom it is dedicated. The electronic part was realised by Hans Tutschku at Harvard University’s electronic studio and is conceived for an 8-channel loudspeaker setup surrounding the audience.
The composition took form after extensive collaboration with Séverine Ballon, whose unique playing and willingness to experiment inspired the composer to realise a piece for and with her. [cf. score, introduction] This collaborative process entailed several sessions at the Harvard University studios, where Mrs. Ballon was a guest in 2015. [Tutschku 2020, Interview, 17:00 – 19:45] Numerous cello sounds were recorded, providing the sound material used in the piece, also containing sounds produced by special playing techniques suggested by Mrs. Ballon. For Hans Tutschku, who has acquired broad experience as an improviser with the “Ensemble für Intuitive Musik Weimar” since the 1980s, working with musicians and investigating the sound material through improvisation are important steps in the process of creating a new composition.
pressure – divided integrates the three fundamental domains of Tutschku’s work as a composer and performer: improvisation, acousmatic music and live electronics. The piece combines both real time processes and fixed sequences precomposed in the studio. To Tutschku, real time processes, while lending presence and immediacy to the electronic sound, also run the risk of remaining merely reactive or compromising sound complexity due to practical reasons. Precomposed material can help to overcome these limitations, extending the possibilities of interaction in view of a “polyphony of thoughts”. [Tutschku 2020, Interview, 14:40]
The search for close interrelations between sound sources and real time transformations is based on the analysis of features of the incoming signal, predominantly the amplitude. These features are then used to control real time processes. This approach can be seen in all of Tutschku’s works with live electronics and is extensively used in pressure – divided. It can be heard e.g. at the beginning of the piece where the intensity of the cello sound defines the quality and degree of spatial diffusion through the octophonic system.
Spatial relations are fundamental in Tutschku’s electronic music and have consequences for both the audience and the performers. These relations concern at least three main aspects: the spatial quality of the sound material itself, the function of space in the conception of performance situations, formal processes and mental imagery, and the characteristics of performance spaces and their use in performance situations.

Characteristic of Tutschku’s spatial conception is the idea of a diffuse sound field:

“I do not want to perceive the speaker as an object from which sound is emitted, but I want a diffuse sound field surrounding us.” [Interview, 47:55]

(“Ich möchte nicht den Lautsprecher als ein Objekt, von dem eben Schall kommt, wahrnehmen, sondern ich möchte ein diffuses Klangfeld, das uns umgibt”. [47:55])

Unorthodox solutions for the positioning of loudspeakers may thus be applied, e.g., turning them against the walls in order to avoid a direct irradiation of the audience.
In pressure – divided spatial awareness is a precondition for the dialogue between instrumentalist and electronics. The cellist’s task is not merely to generate the sound but also to listen to the spatial response. This “openness towards space” as a prerequisite for the performer [22:56] is rooted in a more fundamental concern: the exploration of slowness and reduction.
This concern is already evident in live electronic pieces for solo performers of the same period such as Still Air 1-3 (2013–14) for woodwind instruments and Shadows of Bells (2015) for piano. Besides the reduction in both musical material and the live electronic setup e.g., of the Still Air pieces (Tutschku provides a portable and autonomous setup using smartphones and small loudspeakers), these works are characterised by the absence of pulse, metric structures and fast, gestural figures. Single formal units of durations between 10 and 50 seconds result in very slowly evolving sound processes and sequences.
Slowness and reduction reflect Tutschku’s search for new expressive means:

“Im Kontrast zu anderen meiner Werke, die mit Geschwindigkeit und Virtuosität umgehen, soll dieser Zyklus mit wenig Aktivität eine andere Form von Expressivität erzeugen.” [, Textkommentar zu Still Air 1]
“In contrast to other of my works that deal with speed and virtuosity, this cycle is intended to create a different type of expressivity through little activity.” [, notes on Still Air 1]

This new expressivity necessarily leads to the exploration of very soft dynamic ranges:

“Wenn man über Langsamkeit und Raum und das filigrane Zuhören von Details nachdenkt, dann kommt man automatisch in den leisen Bereich.” [32:50]
“When one thinks about slowness and space and the delicate listening to details, one will automatically get to the quiet region.” [32:50]

pressure – divided follows this approach but expands the expressive range in the opposite direction as well. It could be seen as a juxtaposition of the search for slowness and reduction and a newly reflected gestural brilliance and virtuosity.
This juxtaposition determines the formal disposition. The piece consists of two large sections of approximately the same length. In the first part, instrumental passages exhibit mostly strong dynamics and fast rhythmic figures (e.g. bars 1, 7, 15, 27), fast tempi (q = 94, 110, 82), and a wide tessitura. The second part is predominantly calm, marked by slow tempi (q = 55, 82), passages with long, sustained tones (e.g. bars 2 to 6, 37 to 77) and pitches in the upper range (e.g. bars 37 to 77 and 100 to 112). While the first part contains slow inserts as premonitions of the second part, the latter contains short gestural fragments reminiscent of the first part. The composer refers to both of them as “jumps of thought”, akin to the ability of humans to mentally leave for a moment the present space. [35’53]
This idea is reflected in the title. The term divided can be understood as relating to structural features observed at different levels: the use of extreme registers (the low register extended through scordatura of the C string down to F1, the high register through flageolets up to g4), sharp cuts, extremely contrasting dynamics and tempi, the separation between single musical objects in the second part, as well as the different layers of the electronics.

The complete title pressure – divided, however, is derived from questions raised through personal experience: “How can one remain oneself under great pressure” (“Wie kann man unter grossem Druck selber noch selbst bleiben”). In particular, the composer thought of the challenge of having to embody different “persons” and roles simultaneously in order to cope with the demands of everyday life. [34:27 – 35:04]
This approach reflects Tutschku’s recurrent recourse to mental images, agencies and qualities that enter and leave the creative space and could be regarded as performing scenic actions: “I always think very theatrically in all of my music” (“Ich denke immer sehr theatral in aller meiner Musik”). Images are important in communicating with the performers as well. They help the composer to convey certain attitudes difficult to communicate otherwise. [24:23 – 26:56]
pressure – divided calls for awareness and responsiveness towards the sound space. Rehearsing extensively with the electronic system in the actual space is essential: “the cello part alone would not make any sense whatsoever” (“die Cellostimme alleine würde überhaupt keinen Sinn machen.”) [1:10:00] In this regard, pressure – divided can be seen as exemplary for Tutschku’s live electronic music.

“It is really a kind of give and take. And it is precisely this taking, taking up of what the electronics do in the space at a given moment that is very important to me. It is thus a piece that invites a performer to enter this dialogue with the electronics for once instead of just playing.” [1:11:40]

(“Es ist wirklich eine Art Geben und Nehmen. Und gerade dieses Nehmen, dieses Aufnehmen dessen, was die Elektronik in dem Moment in dem Raum macht, das ist für mich ganz wichtig. Also es ist ein Stück, was ein Musiker vom reinen Spielen einmal weg zu diesem Dialog mit der Elektronik einlädt.”) [1:11:40]


Performance Materials:

a) Score: Babel Score Edition

Date: 2015 (first edition)

b) Other materials: Patch

Source: Hans Tutschku
Date: 16 August 2019
Author: Hans Tutschku
Software: Max/MSP (64 bit / 48 KHz)
Remarks: A standalone version is also available.
File: pressure-divided-max7-64bit-48kHz_1.336.maxpat


Editorial Instructions


The score contains an introduction with information about the creation of the piece, as well as the setup for amplification and control of the electronics:
– Graphic of the complete setup with a flow chart
– Systematic explanation of the operation of the Max/MSP Patch
– Explanations about the notation of the cello part.

With the technique “pinch strings between thumb and index” suggested by Séverine Ballon, the pitch is produced without fingerboard and is therefore less acutely defined. It generates a “pale, clarinet-like sound” [Tutschku 2020, Interview, 21:15]

The notation itself consists of three systems; an upper system with a representation of the bow pressure, a middle system with the notation of the cello part and a lower system showing the control of the cues. These are labelled with roman numerals. The numbers correspond to the bar number where they are to be triggered. The respective electronic procedures are labelled directly next to the cue numbers.


Eight loudspeakers are placed in a circle around the audience. The cello player is positioned in front between speakers 1 and 2.

Two microphones are prescribed:
– 1 DPA miniature microphone near the bridge mainly intended for generating control signals (envelope follower, pitch follower).
– 1 Large-diaphragm condenser microphone. It is also used for amplification and should be routed only to speakers 1 and 2.

A midi pedal is needed on stage, allowing the musician to start the different cues. An audio monitor for the cellist is also prescribed.

Fig. I.
Fig. I. From score, introduction.

Max patch

The electronic part runs on a Max/MSP patch. A standalone version is also available. The patch starts with a wizard setup. All the important setup steps are listed in 12 points and are to complete before accessing the performance interface.
The performance patch allows to control three parameters: Reverb, sound files (sf), live electronics (treatment). It should be noted that the parameter reverb also controls the reverb of the sound files and not only the reverb of the live cello. If the piece is played in an ideal situation there is no need to drastically adjust the levels of the three faders [c.f. Tutschku 2020, Interview, 53:00]. The faders are meant to compensate for any non-ideal conditions e.g. due to room acoustics or audience absorption.
In the performance interface it is also possible to adjust the mic gain, however, this parameter is not implemented on the midi controller. The two microphones are summed in the DSP patcher and then used as a mono signal for the different transformations. The patchers munger and one delay are fed directly the patchers gizmo and reverb are fed from the patcher mic input, where the gain sends for these modules are automated.
The transformations are organised in modules. In the patcher p status it is possible to see which modules are active in the current cue.

Fig. II
Fig. II. Patch modules

Performance report

The concert took place on 17 January 2020 at ZHdK at the concert hall No. 1 (KS 1), with Martina Schucan, cello, Carlos Hidalgo, sound projection, and Leandro Gianini, sound engineering.


Eight L-Acoustics 8 XT and one Meyersound 700-HP subwoofer were used. In an earlier phase, the eight speakers were hung on trusses at approximately 5 – 6 metres height. After some experimenting it was decided to place the speakers on stands at ca. two metres above the floor. The listening experience was clearer from the audience’s perspective, but also allowed the performer to better hear the live electronic part.
One additional L-Acoustics 8XT was used as a monitor for the cellist.
The composer pointed out that in some situations he used a configuration with the speakers facing the walls and not directly the audience [c.f. above, Introduction]. As the placement of the speakers facing the audience proved satisfying in this instance, the second approach was not tried out.
The subwoofer was placed between speakers 1 and 2. The signal of the eight channels was sent from the desk to the subwoofer at a low level.
A DPA 4099 mounted on the instrument and a TLM 103 on a little stand were used for microphones. The score does not precisely specify the placement, but the composer pointed out his preferred placement of the large diaphragm microphone, which is shown below.

Fig. III
Fig. III. Placement of diaphragm microphone

In more recent pieces such as as Herkunft -entschlüsseln – entbehren (2019) for cello and 9-channel electronics the composer uses a separate speaker near the instrumentalist for amplification of the instrument, instead of routing the signal to speakers 1 and 2. In this way, a better sense of localisation can be obtained, and this approach can also be taken for pressure — divided .
Amplification was almost not necessary in this performance because of the room size and the use of a cello resonance podium. The acoustical signal coming from the instrument was well audible and just amplified slightly on speakers 1 and 2. The level was low enough, and the speakers placed far enough behind the player so as not to cause confusion in the localisation.
In the section from bar 153 to the end some feedback issues with low frequencies occurred. For this section the input gain of the microphones was then slightly reduced.


To check the level of the samples we used the following cues:
Cue 1 mf
Cue 2 f
Cue 99 ff (Loudest)

To check the live electronic reaction, we used cues 1 and 19. Cue 19 is especially important, because in this long crescendo the dynamics of the player directly affects the live transformation. Due to the long progression, it is easier to hear the relationship between action and reaction.


The electronic part is divided into 36 cues which the player starts with a midi pedal according to the score. The cues are not numbered in linear fashion, the numbering corresponding to the bar number in which the event occurs. This facilitates the communication during rehearsals.


We used a monitor with a very low level, since the signal coming from the eight speakers was well audible also for the performer. The use of an audio monitoring system might prove more critical in a bigger room or in a more reverberant room.

The current cue status can be displayed on an iPad running MIRA and synchronised with Max/MSP. After discussing this with the performer, it was decided not to use this feature.


It proved essential for the cellist to be able to rehearse with the full electronic setup early into the learning process in order to better understand the relationship between the cello and the electronic part. [c.f. Introduction]

Sound Projection

As the composer pointed out, live electronics processing in pressure – divided does not have to be adjusted during performance, as all electronics processing is provided within the patch and has been appropriately mixed at the studio. The most important goal is to achieve an optimal balance between the acoustic amplified signal and the live electronics.

“Once you have found the volume for the electronics, you can play through without doing anything on the three faders.” [Tutschku 2020, Interview, 55:10 – 55:20]

However, Tutschku recommends giving special attention to some specific sections in order to achieve a good balance between the acoustic sound and the electronics. These sections are:

-Bar 19. The crescendo should not be reinforced. The change in dynamics will be influenced directly by the cellist. Moreover, there is a sound file produced at the studio already taking into account the highest sound level that could be produced by the live electronics.
-Bars 38 to 40 and bars 75 to 76. The crescendo in the cello could be reinforced carefully, depending on the dynamic intensity of the live playing.
-Bar 99. Here the climax of the whole piece occurs. The crescendo can be reinforced just six bars before, in order to emphasise this moment just a little bit.
-Bar 131 until the end of the piece. The reverb effect may be used very carefully, (only) if the concert hall has dry acoustics. However, the reverb fader should not be used if the piece is played in a large concert space with big resonance.

In general, stronger amplification of the electronics can be considered if there is a large audience in the concert hall, which normally impacts acoustic conditions in a space. The same would apply if the piece were to be performed in a large concert hall.

Remarks by Martina Schucan

Performative challenges in Hans Tutschku’s pressure-divided

For me as a performer, a fascinating aspect in working on Hans Tutschku’s pressure – divided is the complex interaction with the electronics. It is worthwhile to explore the different ways of playing that are either prescribed, can be influenced by the performer or have to be developed independently, and to take the necessary time to rehearse with the electronics.
In the following, I would like to describe some of the different compositional elements.
A main element in the piece are long tones with a development of dynamics and timbre (e.g. bars 19 or 38). Here the task is first to establish one’s own sound and then to perceive how the mixture of the intensifying sound and the electronic development creates a tension, enriching the purely instrumental possibilities many times over. This intensification not only affects the volume, but also the texture of the sound. Together with the cello’s timbral possibilities using tasto, ponticello or col legno playing, or applying excessive pressure, a lively, oscillating tonality results.
As another important element, I would like to point out the percussive Bartók pizzicato (e.g. from bar 48). With these impulses hitting the fingerboard, the player only influences the time, but not the content of the triggered electronic event. The pizzicati are played on a C string tuned a fourth lower. During rehearsals, we looked on the one hand for the optimal way of hitting the fingerboard; on the other hand, the passages became increasingly lively, the more I became able to perceive the unpredictable electronic reactions in addition to concentrating on my part.
Between the Bartók pizzicati there are passages with high harmonics, the dynamic gradation of which must be explored very carefully so that the layers of live playing, live electronics and fixed sound files enter into a perceivable interplay.
From bar 78, the cello plays highly virtuosic melodies with lively bow articulation, constantly moving bow stroke positions and dynamic developments. At this point, one is practically playing chamber music with the electronics. It is very helpful to listen to the electronic track alone before playing one’s own part. Our goal was to achieve a certain transparency despite the many layers of sound and the high level of activity, which cedes to an over-intensity only towards the end of the passage.
After this climax, the cello finds its way back to a delicate harmonic line, first electronically supported, then suddenly standing alone without any resonance in the space. I would describe this passage as the emotional climax of the work.
After that, the different sound spheres are presented side by side within shorter units. The aim here is to allow enough time and space for each sound. Above all, the sense of space that arises with each impulse creates an expressive world. As a performer, I communicate with an imaginary space.
The final part is characterised by a special playing technique in which the left hand does not press the string down but pulls it up with two fingers. The result is a flute-like, incredibly appealing timbre. At first, a melody can be clearly perceived. Towards the end, it becomes more and more punctuated by breaks. If one succeeds to imagine the melody going on during the breaks, a feeling of temporal and spatial eternity arises.

July 7, 2020 / Martina Schucan

Selected Bibliography

Tutschku, Hans (2020): Lecture. Given at ZHdK, 16 January 2020.

Tutschku, Hans (2020): Interview. Conducted by Germán Toro Pérez, 15 January 2020.

Tutschku, Hans (no year): Commentary on Still Air 1. Online: (last accessed on 4 August 2021)

Composer’s website: (last accessed on 4 August 2021)

Schematic Overview